CN107269423B

CN107269423B - Thrust reverser cellular board load distribution system and method

Info

Publication number: CN107269423B
Application number: CN201710145002.3A
Authority: CN
Inventors: F·克列晓夫; K·托马斯; B·P·唐; M·马费奥; R·S·法雷尔
Original assignee: Boeing Co
Current assignee: Boeing Co
Priority date: 2016-03-31
Filing date: 2017-03-13
Publication date: 2022-04-19
Anticipated expiration: 2037-03-13
Also published as: CA2956193A1; EP3225795B1; US10309434B2; ES2765809T3; EP3225795A1; BR102017003969A2; BR102017003969B1; JP2017214920A; CA2956193C; JP6944250B2; CN107269423A; US20170284338A1

Abstract

Systems and methods for an aircraft propeller (100) thrust reverser having a fastening system are provided. The fastening system may include a male conduit (350) and a female conduit (352) configured to be threaded into the male conduit (350). The male (350) and female (352) conduits may be coupled to the honeycomb and may distribute forces evenly to the honeycomb to prevent plastic deformation of the honeycomb core of the honeycomb.

Description

Thrust reverser cellular board load distribution system and method

Technical Field

The present disclosure relates generally to aircraft and more particularly to aircraft thrust reversers and load sharing by cellular panels.

Background

Thrust reversers for aircraft propellers typically include an inner wall and an outer wall. The inner wall may be located proximate to a core engine of the aircraft propeller. As the core engine power of aircraft propellers increases, the heat generated by the engine also typically increases. The inner wall located close to the core engine may also be subjected to higher temperature levels. The inner wall may be attached to other structures of the aircraft. However, conventional techniques for creating coupling features for attaching the inner wall to other structures of the aircraft may be ineffective due to high temperatures.

Disclosure of Invention

Systems and methods for thrust reverser cellular board load distribution are disclosed herein. In certain examples, an aircraft propeller may be provided. An aircraft propeller may include a core engine and a thrust reverser. The thrust reverser may include an inner wall located proximate to the core engine. The inner wall may include a honeycomb structure including a first panel, a second panel, a honeycomb core disposed between the first panel and the second panel, and a bore, and a fastening system disposed within the bore. The fastening system may include a male and female conduit. The male conduit may include a male conduit body, wherein an external threaded portion is disposed on at least a first end of the male conduit body, a male throughbore is disposed within the male conduit body, and a male flange portion is disposed on a second end of the male conduit body, the male flange portion being coupled to the first panel and configured to distribute loads to the honeycomb structure. The female conduit may include a female conduit body with an internal threaded portion disposed on at least a first end of the female conduit body and coupled to the external threaded portion to secure the male and female conduits to the honeycomb, a female throughbore disposed within the female conduit body, and a female flange partially disposed on a second end of the female conduit body, the female flange coupled to a second panel and configured to distribute loads to the honeycomb.

In certain other embodiments, a fastening system for a structure may be provided. The fastening system may include a male and female conduit. The male conduit may include a male conduit body, wherein an external threaded portion is disposed on at least a first end of the male conduit body, a male throughbore is disposed within the male conduit body, and a male flange portion is disposed on a second end of the male conduit body and is configured to couple to a first panel of the honeycomb and distribute a load to the honeycomb when the male flange portion is coupled to the first panel. The female conduit may include a female conduit body, wherein an internal threaded portion is disposed on at least a first end of the female conduit body and is configured to couple to the external threaded portion to secure the male and female conduits to the honeycomb, a female throughbore is disposed within the female conduit body, and a female flange portion is disposed on a second end of the female conduit body and is configured to couple to a second panel of the honeycomb and distribute load to the honeycomb when the female flange portion is coupled to the second panel.

The scope of the invention is defined by the claims, which are incorporated into this section by reference. A more complete understanding of the present disclosure will be afforded to those skilled in the art, as well as a realization of additional advantages thereof, by a consideration of the following detailed description of one or more embodiments. Reference will be made to the accompanying drawings, which are first briefly described.

Drawings

Fig. 1 shows a perspective view of an aircraft propeller according to an example of the present disclosure.

Fig. 2 illustrates a side cutaway view of an aircraft propeller according to an example of the present disclosure.

Figure 3 illustrates a side cross-sectional view of a honeycomb structure and a honeycomb fastening system according to an example of the present disclosure.

Fig. 4 shows a side cross-sectional view of a male conduit according to the present disclosure.

Fig. 5 shows a side cross-sectional view of a female conduit according to an example of the present disclosure.

Fig. 6 is a flow chart detailing the assembly of an auxiliary structure to a honeycomb structure according to an example of the present disclosure.

Examples of the present disclosure and its advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures.

Detailed Description

In accordance with one or more examples, systems and techniques for a fastening system for distributing point loads through cellular boards are described in the disclosure herein. In some examples, the honeycomb panel may be a panel of an aircraft propeller. For example, the honeycomb panel may be part of a thrust reverser for an aircraft propeller. In this example, the honeycomb panel may be an outer wall, an inner wall, or another portion of the thrust reverser.

The fastening system may include a male and female conduit. The male conduit may include a male conduit body, which may include an externally threaded portion disposed on a cylindrical or substantially cylindrical portion of the male conduit body and also include a male flange portion. The female conduit may comprise a female conduit body which may comprise an internally threaded portion disposed on a cylindrical or substantially cylindrical portion of the female conduit body and further comprises a female flange portion. The male conduit may be inserted into the hole of the honeycomb panel from one end, and the female conduit may be inserted into the hole from the other end. The male and female conduits may be coupled to each other by, for example, being screwed onto each other. The male flange portion may contact a first panel of the honeycomb structure and the female flange portion may contact a second panel of the honeycomb structure opposite the first panel. The male and female spools may be threaded to a specified torque value. The forces exerted by the tightening of the male conduit to the female conduit and/or the forces from the tightening of the fasteners to the male and/or female conduits may be transmitted to the honeycomb.

Fig. 1 shows a perspective view of an aircraft propeller according to an example of the present disclosure. The aircraft propeller 100 may include a nacelle (nacellee) 102, a thrust reverser door 124, and a fan 136. In the example shown in FIG. 1, the nacelle 102 may contain a fan 136, but other examples of aircraft propellers may arrange the fan such that it is not contained by the nacelle (e.g., in a turboprop configuration). The fan 136 may draw in and/or energize air flowing into the nacelle 102, such as in the airflow direction 140A. Air flowing into nacelle 102 via airflow direction 140A may flow through various internal flow paths within nacelle 102. When aircraft propeller 100 is in the thrust reversal configuration, air flowing into nacelle 102 in airflow direction 140A may be redirected to another direction to provide reverse thrust.

When the aircraft propeller 100 is operating normally (e.g., providing thrust), the thrust reverser doors 124 may be in a closed position that blocks the thrust reverser apertures (shown in fig. 2 as thrust reverser apertures 132) thereby sealing or substantially sealing the thrust reverser apertures such that no or minimal airflow passes through the thrust reverser apertures 132. When the aircraft propeller 100 is in the thrust reversal configuration (e.g., providing a reverse thrust to, for example, slow down an aircraft 50 to which the aircraft propeller 100 may be attached), the thrust reverser doors 124 may be in an open position that does not block the thrust reverser apertures 132, allowing air to flow through the thrust reverser apertures 132. In certain examples, the thrust reverser doors 124 may form the thrust reverser apertures 132 when the thrust reverser doors 124 are in an open configuration. In this example, when the thrust reverser doors 124 are in the closed configuration, the thrust reverser apertures 132 may be absent.

Fig. 2 illustrates a side cutaway view of an aircraft propeller according to an example of the present disclosure. The aircraft mover 100 shown in FIG. 2 may include a nacelle 102 having a bullnose 206, a thrust reverser door 124, a core engine 248, a thrust reverser cascade 210, a cascade support ring 208, a thrust reverser aperture 132, and a blocker door 214. The core engine 248 and/or the nacelle 102 may at least partially define a bypass flow path 256. Air energized by the fan 136 may flow through the bypass flow path 256. During normal operation, energized air may flow out of the exhaust of nacelle 102, but during thrust reversals, the energized air may be diverted by blocker doors 213 and flow out of nacelle 102 through thrust reverser cascade and thrust reverser orifices 132.

Nacelle 102 can be similar to the nacelle described in FIG. 1. The nacelle 102 in fig. 2 may additionally include a bullnose 206. The bullnose 206 may be any structure that may be coupled to one end of the thrust reverser cascade 210. In certain examples, the bullnose 206 may extend from another portion of the nacelle 102 and may form a protrusion of the nacelle 102. As shown in FIG. 2, at least the portion of the bullnose 206 facing the core engine 248 may include a smooth curved surface (radius'd surface). This arcuate surface may allow for smooth airflow from bypass flow path 256 through thrust reverser cascade 210 and, therefore, allow for higher mass flow through thrust reverser cascade 210. When in the closed position, a surface of the thrust reverser door 124 may be configured to be placed adjacent to or coupled to a portion of the bullnose 206. Thus, when in the closed position, the thrust reverser doors 124 may form a smooth or substantially smooth surface with the interior surface of the nacelle 102 to allow for a smooth airflow within the aircraft propeller 100 when the thrust reverser doors 124 are in the closed position. In certain examples, the thrust reverser door 124 may include an inner wall and an outer wall.

FIG. 2 further illustrates the open and closed positions of the thrust reverser door 124. As shown, the thrust reverser doors 124 may be in an open position 124B and a closed position 124A. The thrust reverser doors 124 may be configured in other positions in other examples. Further, other examples may include non-translating thrust reverser doors (e.g., thrust reverser doors that are rotatable between open and closed positions, among others) and thrust reverser doors that are otherwise open and closed (e.g., by louvers, by deployment of air deflectors, or by other means).

In the closed position 124A, the thrust reverser door 124 may allow air to flow through the bypass flow path 256 of the aircraft mover 100 and out of the bypass flow path 256 through the exhaust to provide thrust. The bypass flow path 256 may be at least partially defined by portions of the core engine 248 and/or the nacelle 102. The air flowing through the bypass flow path 256 may be energized by the fan 136, may flow generally in the airflow direction 140A, and may provide thrust (or reverse thrust) to power an aircraft to which the aircraft propeller 100 is attached. The core engine 248 may power the fan 136, and the fan 136 may energize air flowing through the bypass flow path 256.

When the thrust reverser door 124 is in the closed position 124A, the blocker doors 214 may be positioned to unblock or minimally block (e.g., less than a 5% limit of the total airflow within the bypass flow path 256) the airflow within the bypass flow path 256.

In the open position 124B, the thrust reverser door 124 may allow air to flow through the thrust reverser aperture 132. In certain examples, when the thrust reverser doors 124 are in the open position 124B, the blocker doors 214 may also move into a position that blocks at least a portion of the bypass flow path 256 to divert airflow within the bypass flow path 256 through the thrust reverser apertures 132. This diverted airflow may flow at least partially in the airflow direction 140B or in a direction generally in the airflow direction 140B. Air flowing in the airflow direction 140B may provide a reverse thrust.

The diverted airflow may flow through the thrust reverser cascade 210. The linear thrust reverser cascade 210 shown in FIG. 2 may be a linear thrust reverser cascade. Although FIG. 2 illustrates a side cutaway view of thrust reverser cascade 210, thrust reverser cascade 210 may be circumferentially disposed and/or offset from, for example, core engine 248 or another portion of aircraft mover 100. For example, thrust reverser cascade 210 may "wrap around" core engine 248. Additionally, the thrust reverser cascade 210 may extend linearly, or substantially linearly, from the bullnose 206 to the cascade support ring 208. The bullnose 206 and/or cascade support ring 208 may be coupled to a thrust reverser cascade 210. The bullnose 206 and/or cascade support ring 208 may support and/or hold in place the thrust reverser cascade 210. In some such examples, the cascade support ring 208 may be attached to other structural features of the aircraft propeller 100.

Figure 3 illustrates a side cross-sectional view of a honeycomb structure and a honeycomb fastening system according to an example of the present disclosure. Fig. 3 includes a honeycomb structure having a first panel 360, a second panel 362 and a honeycomb core 358 and a honeycomb fastening system having a male conduit 350, a female conduit 352, a bolt 354 and a nut 356. Additionally, the various examples of fig. 3 may also include a spacer 366, an auxiliary structure 368, and a spacer 364.

The honeycomb structure includes a first panel 360, a second panel 362, and a honeycomb core 358. The honeycomb core 358 is disposed between a first panel 360 and a second panel 362. In certain other examples, additional elements may be disposed between the first panel 360, the honeycomb core 358, and/or the second panel 362. In certain examples, the first panel 360, the second panel 362, and/or the honeycomb core 358 may all be constructed from the same material, although other examples may construct the first panel 360, the second panel 362, and/or the honeycomb core 358 from a plurality of different materials. Such materials may be, for example, metals such as steel, aluminum, titanium, tungsten, copper, and other metals; composite materials such as fiberglass, carbon fiber, Kevlar (Kevlar) and other composite materials, plastics, wood, glass and other suitable types of materials. For example, in certain examples, the first panel 360, the honeycomb core 358, and the second panel 362 can each be constructed of at least titanium. In certain other examples, the first panel 360 and the second panel 362 may be constructed from a combination of carbon fibers and kevlar, but the honeycomb core 358 may be constructed from carbon fibers only. In certain such examples, the coefficients of thermal expansion of the honeycomb and the male and/or female conduits may be substantially similar (e.g., within 20% or less). Thus, the honeycomb structure may comprise the same material as the male and/or female conduits (e.g., both formed of titanium), or may comprise a material having a substantially similar coefficient of thermal expansion.

The male conduit 350 includes a male conduit body. At least a portion of the male conduit body may be cylindrical or substantially cylindrical. The male conduit body includes an externally threaded portion disposed on a cylindrical or generally cylindrical portion of the male conduit body. In addition, the male conduit body includes a male flange portion. The male flange portion is configured to transmit a force to a first panel 360 of the honeycomb structure when attached to the honeycomb structure. The male conduit 350 may be further described in fig. 4.

The female conduit 352 includes a female conduit body. At least a portion of the female conduit body may be cylindrical or substantially cylindrical. The female conduit body includes an externally threaded portion disposed on a cylindrical or generally cylindrical portion of the female conduit body. In addition, the female conduit body includes a female flange portion. The female flange portion is configured to transfer a force to the second panel 362 of the honeycomb structure when attached to the honeycomb structure. The female conduit 352 may be further described in fig. 5.

The male and

female conduits

350, 352 may be coupled by screwing the externally threaded and internally threaded portions together. In certain embodiments, the male and

female conduits

350, 352 may be coupled without the need for, for example, welding, potting, or crushing the honeycomb core 358. Thus, the fastening of the male and

female conduits

350, 352 can be accomplished reproducibly with minimal testing and at high productivity. The fastening may not damage the honeycomb structure (e.g., may not crush the honeycomb core 358 and/or plastically deform the honeycomb core 358). In addition, the fastening of the male and

female conduits

350, 352 may allow the fastening system to withstand higher temperatures, such as 300 degrees celsius or less, 500 degrees celsius or less, 1000 degrees celsius or less, or over 1000 degrees celsius. As such, the fastening system may not include potting compounds or other adhesives that may melt or weaken at such high temperatures. The absence of such adhesives may allow the fastening system to withstand higher temperatures.

The ability to withstand higher temperatures may be beneficial in certain applications. For example, the thrust reverser doors 124 may include portions, such as inner walls, that may be located near or facing the core engine 248. Such portions may be exposed to high temperatures, and thus, the fastening systems disclosed herein may withstand such higher temperatures.

The conduits can be screwed together to a specific torque value. Forces generated by screwing the conduits together and/or forces from any fasteners (e.g., bolts 354) installed using the conduits may be transferred to the honeycomb structure via the male flange portion and/or the female flange portion. Thus, the male flange portion of the male conduit 350 may transmit the force received by the male conduit 350 to the first panel 360, and the female flange portion of the female conduit 352 may transmit the force received by the female conduit 352 to the second panel 362. In examples where the bolt 354 and nut 356 are secured to the conduit, the load may thus be transferred from the bolt 354 through the conduit wall into the first panel 360 and/or the second panel 362. The male and/or female flange portions may be sized such that loads may be transferred over a sufficiently large area of the first panel 360 and/or the second panel 362 to prevent deformation and/or plastic deformation of the honeycomb core 358.

Some examples may also include a shim 366. The spacer 366 may, for example, cover one of the male conduit 350 and/or the female conduit 352. In the example shown in fig. 3, the female conduit 352 may be inserted into the bore of the second panel 362. The spacer 366 may then be placed, assembled, and/or coupled to the second panel 362. The spacer 366 may cover at least a portion of the female conduit 352. The spacer 366 may, for example, further hold the female spool 352 in place and/or may be a honeycomb structure and/or a heat shield for the female spool 352. Other examples may include additional shims that may cover the other of the male and/or

female conduits

350, 352.

Some examples may include a baffle 364. The spacer 364 may be the same or similar in thickness to the flange portion of the female conduit 352. The spacer 364 may allow the spacer 366 to sit flush on top of the spacer 364. The bulkhead 364 may comprise a cutout containing a flange portion of the female conduit 352. Thus, the spacer 366 can rest on the diaphragm 364 and the female conduit 352.

The nut 356 may be coupled to the secondary structure 368. The auxiliary structure 368 may be a component of, for example, an aircraft propeller 100, and/or a thrust reverser door 124. The auxiliary structure 368 may be attached to the honeycomb. Thus, the bolt 354 may include a head and a shank, and may be inserted into the through-holes of the male and

female conduits

350, 352, and then through the hole of the auxiliary structure 368. A nut 356 may be attached to the bolt 354 at one end (e.g., a threaded end) to clamp or otherwise couple the secondary structure 368 to the honeycomb. In some such examples, the clamping force from the bolts 354 may be distributed to the male spool 350, and then evenly distributed from portions of the male spool 350 to the honeycomb. In the embodiment shown in fig. 3, the nut 354 may be shaped such that when inserted into the male conduit 350, the head of the bolt 354 is flush with the surface of the male conduit 350. In some examples, the bolt 354 and/or the nut 356 may additionally include one or more washers or other devices to more evenly distribute the clamping force. Additionally, loads may be transferred from, for example, the auxiliary structure 368 to the honeycomb structure via the female conduit 352.

In certain examples, the auxiliary structure 368 may be a highly loaded component of the aircraft. As such, loads from the auxiliary structure 368 may be transferred into the honeycomb structure via the fastening system. The shim 366 and/or the spacer 364 may aid in the transfer of loads from the auxiliary structure 368 by closing the gap between the auxiliary structure 368 and the honeycomb, and thus allow a load path from the auxiliary structure 368 to the honeycomb. In addition, the spacer 366 and/or the spacer 364 reduce the preload within the fastening system. In certain examples, shims 366 may also allow auxiliary structure 368 to be precisely positioned relative to the fastening system and/or additional components of the aircraft or aircraft mover, for example, by allowing the distance between such components to be varied via stacking or removing shims.

Fig. 4 shows a side cross-sectional view of a male conduit according to the present disclosure. The male conduit 350 may include a male conduit body. The male conduit body may include a male flange portion 470, a male shank portion 472, a male through bore 474, a chamfer 476, and a male shoulder 478.

The male stem portion 472 may be located on the first end of the male conduit body. The male handle portion 472 is insertable into a hole within the honeycomb. The male handle portion 472 can be threaded, for example, onto a threaded portion of the female conduit 352.

The male flange portion 470 may be located on the second end of the male conduit body and may be configured to be coupled to a panel of the honeycomb structure (e.g., the first panel 360). The male flange portion 470 may evenly distribute the force from the male spool 350 to the honeycomb. The male flange portion 470 may be sized, for example, in response to an expected force being distributed to the male conduit 350, such that the expected force is transmitted to a sufficiently large area of the honeycomb to prevent significant deformation and/or plastic deformation of the honeycomb and/or the honeycomb core 358. For example, where the male flange portion 470 and the male shank portion 472 are generally circular in cross-section, the male flange diameter 492 may be expressed as a ratio to the male shank diameter 490. In certain embodiments, the ratio may be less than 2 to 1, less than 3 to 1, less than 5 to 1, less than 10 to 1, less than 20 to 1, or 20 to 1 or greater. In examples where the cross-section of the male flange portion 470 and/or the male shank portion 472 is not substantially circular, the ratio may be expressed as a ratio of the cross-sections between the male flange portion 470 and the male shank portion 472.

In certain examples, the male flange portion 470 may be configured to transfer out-of-plane loads (e.g., clamping and/or tension loads transferred by bolts, nuts, and/or other structures such as the secondary structure 368). The male flange portion 470 may receive such loads and transfer the loads to the honeycomb structure (e.g., the first panel 360).

The through bore 474 may be disposed within the male conduit body. The through-hole 474 may allow a portion of the bolt 354 to pass through the male conduit 350. The through bore 474 may extend from the first end to the second end of the male conduit body. In some examples, the through-holes 474 may be substantially smooth such that the bolts 354 pass through the through-holes 474 without threading into the through-holes 474. In examples where the male conduit 350 is configured to receive a bolt having a head configured to be flush with the male conduit 350, the male conduit 350 may additionally include a chamfer 350 on one or both ends of the through bore 474. The chamfer 350 may allow the head of the bolt 354 to become flush when inserted into the male conduit 350.

Some examples of the male conduit 350 may include a male shoulder 478. The male shoulder 478 may be sized, for example, to help position the male conduit 350 within the bore of the honeycomb structure. Some examples of the male shoulder 478 may include chamfers, circles, and/or other features to aid in insertion of the male conduit 350 into the bore.

In certain examples, the male shoulder 478 may transfer in-plane loads (e.g., bearing loads) received by the male conduit 350 to a honeycomb structure coupled to the male conduit 350. Transmitting such loads through the male shoulder 478 may reduce and/or eliminate bending of the male conduit 350 and/or any bolts or nuts attached to the male conduit 350. In certain examples, the height of the male shoulder 478 (i.e., the dimension of the y-axis of the male shoulder 478 as shown in fig. 4) may be equal to or greater than the thickness of the panel to which the male conduit 350 is configured to be coupled. In some such examples, certain sides of the male shoulder 478 may be parallel to certain sides of the aperture of the panel to which the male conduit 350 is configured to be coupled. Further, the diameter of the male shoulder 478 may be sized according to the expected load to transmit forces over a sufficiently large support area such that the transmission of forces does not result in deformation or plastic deformation of the panels and/or any other portions of the honeycomb. In certain examples, the diameter of the male shoulder 478 may be expressed as a ratio to the diameter of the male shank portion 472. In certain examples, the ratio may be less than 1.1 to 1, less than 1.5 to 1, less than 2 to 1, less than 3 to 1, less than 5 to 1, or 5 to 1 or greater.

Fig. 5 shows a side cross-sectional view of a female conduit according to an example of the present disclosure. The female conduit 352 may include a female conduit body. The female conduit body may include a female flange portion 580, a female stem portion 582, a female throughbore 584, and a female shoulder 586.

The female handle portion 582 can be located on the first end of the female conduit body. The female handle portion 582 may be threaded and may be configured to be inserted into a hole within the honeycomb and threaded onto the threaded portion of the male conduit 350. Thus, the threaded portion of the female handle portion 582 may be threaded to mate with the threaded portion of the male handle portion 472. Threading the male and

female conduits

350, 352 together may allow the male and

female conduits

350, 352 to be coupled together and mechanically fastened to the honeycomb. In certain examples, the male and

female conduits

350, 352 may be mechanically fastened to the honeycomb structure without the use of adhesives, such as potting compounds, and/or without the use of welding or other auxiliary assembly steps.

The female flange portion 580 may be located on a second end of the female conduit body and may be configured to be coupled to a panel of a honeycomb structure (e.g., the second panel 362). The female flange portion 580 may evenly distribute the force from the female conduit 352 to the honeycomb structure. Further, the female flange portion 580 may be sized, for example, in response to an expected force being distributed to the female conduit 352, such that the expected force is transmitted to a sufficiently large area of the honeycomb so as to prevent significant deformation and/or plastic deformation of the honeycomb and/or the honeycomb core 358. For example, where the female flange portion 580 and the female handle portion 582 are generally circular in cross-section, the female flange diameter 594 may be expressed as a ratio to the female handle diameter 596. In certain such embodiments, the ratio may be less than 2 to 1, less than 3 to 1, less than 5 to 1, less than 10 to 1, less than 20 to 1, or 20 to 1 or greater. Further, in examples where female flange portion 580 and/or female handle portion 582 does not include a generally circular cross-section, the ratio may be expressed as a ratio of cross-sectional areas between female flange portion 580 and female handle portion 582.

A through bore 584 may be provided within the female conduit body, the through bore 584 being similar to the through bore 474 of the male conduit body. The through hole 584 may allow a portion of the bolt 354 to pass through the female conduit 352. The through bore 584 may extend from the first end to the second end of the female conduit body. In some examples, the through-hole 584 may be substantially smooth such that the bolt 354 may pass through the through-hole 584 without being threaded into the through-hole 584.

Additionally, the through-hole 584 may include a through-hole shoulder 588. The through bore shoulder 588 may be configured to transfer loads experienced by the bolt, such as support loads, to the honeycomb structure via the female conduit 352. In certain examples, the through-hole shoulder 588 may comprise an inner diameter similar to the diameter of the bolt shank that the through-hole 584 is configured to receive. Thus, when loaded, moved, or deflected, the bolt may contact the through-hole shoulder 588 and transfer the load to the through-hole shoulder 588. Thus, the load may be transferred from the bolt to the through-hole shoulder 588 and to the honeycomb structure. This load transfer may prevent significant bending of the bolt under the bolt. In certain examples, the through bore 474 of the male conduit 350 may alternatively or additionally include a through bore shoulder. In other examples, the through bore 474 of the male spool 350 may be sized to act as a shoulder to transmit loads and prevent deformation or significant deformation of the bolt.

In certain examples, the female conduit 352 may also include a female shoulder 586. The female shoulder 586 may be sized, for example, to help position the female conduit 352 within the bore of the honeycomb structure. Certain examples of the female shoulder 586 may include features similar to the male shoulder 478, including chamfers, circles, and/or other features to aid in insertion of the female conduit 352 into the bore. Further, the female shoulders 586 can transfer in-plane loads (e.g., bearing loads) received by the female conduit to the honeycomb coupled to the female conduit. Transferring such loads may reduce and/or eliminate bending of the female conduit and/or any bolts or nuts attached to the female conduit.

In certain examples, the height of the female shoulder 586 can be equal to or greater than the thickness of the panel to which the female conduit 352 is configured to be coupled. Further, in some such examples, certain sides of the female shoulder 586 may be parallel with certain sides of the aperture of the panel. Additionally, the diameter of the female shoulder 586 and/or the through-hole shoulder 588 may be sized according to the expected load to transmit force over a sufficiently large support area such that transmission of this force does not result in deformation or plastic deformation of the panel. In certain examples, the diameter of the female shoulder 586 can be expressed as a ratio to the diameter of the female stem portion 582. In certain examples, the ratio may be less than 1.1 to 1, less than 1.5 to 1, less than 2 to 1, less than 3 to 1, less than 5 to 1, or 5 to 1 or greater.

Fig. 6 is a flow chart detailing the assembly of an auxiliary structure to a honeycomb structure according to an example of the present disclosure. In block 602, a male conduit may be inserted into a hole of a honeycomb. In block 604, a female conduit may be inserted into the bore of the honeycomb.

In block 606, the male and female conduits may be coupled together by threading the threaded portions of the male and female conduits together. In certain embodiments, the male and female conduits may be threaded together to a specific torque to couple to the honeycomb and distribute the load to the honeycomb. In certain examples, the male and female conduits may be coupled together without adhesive, without welding, or other techniques that may not be more labor intensive and/or may not lead to failure at high temperatures.

In block 608, after the male and female conduits have been inserted into the bores and coupled together, bolts may be inserted into the through-bores of the male and/or female conduits. The bolt can be inserted without being screwed into the through-hole of the male and/or female conduit. The bolt may include a head and a shank. The head may contact one end of the through hole(s). Structures of the aircraft (e.g., structures associated with thrust reversers) may be coupled to the other end of the through-hole(s). The bolt may pass through the through hole(s) for insertion into the hole of the structure.

In block 610, a nut may be threaded onto the bolt. The nut may hold the structure in place when screwed onto the bolt. Thereby, the structure may be arranged between the honeycomb structure and the screw cap. In some examples, the nut may be screwed to a particular torque value to securely couple the structure to the honeycomb structure. In certain examples, a particular torque value may crush the honeycomb core 358 of the composite honeycomb structure even with washers that transmit load. In such examples, the fastening system may provide a rigid column to transfer loads from the torque and thus avoid crushing and/or plastic deformation of the honeycomb structure.

Further, the present disclosure includes embodiments according to the following clauses:

clause 1. an aircraft propeller, comprising:

a core engine; and

a thrust reverser including an inner wall positioned proximate to a core engine, the inner wall including:

a honeycomb structure comprising a first panel, a second panel, a honeycomb core disposed between the first panel and the second panel, and a cell, an

A fastening system disposed within the aperture, the fastening system comprising:

a male conduit comprising a male conduit body, wherein:

an externally threaded portion is disposed on at least the first end of the male conduit body,

the male through hole is provided in the male conduit body, an

A male flange portion disposed on the second end of the male conduit body, coupled to the first panel, and configured to distribute a load to the honeycomb;

and

a female conduit comprising a female conduit body, wherein:

an internally threaded portion is disposed on at least the first end of the female conduit body and is coupled to the externally threaded portion to secure the male and female conduits to the honeycomb,

a female through-hole is provided in the female spool body, an

A female flange portion is disposed on the second end of the female conduit body, coupled to the second panel, and configured to distribute a load to the honeycomb.

Clause 2. the aircraft propeller of clause 1, wherein the male and female conduits are mechanically fastened to the honeycomb structure without the need for an adhesive.

Clause 3. the aircraft propeller of clause 1, the fastening system further comprising:

a bolt including a head and a shank and disposed through the male and female through-holes; and

a nut fastened to a shank of the bolt, wherein the male and/or female flange is configured to distribute a load received from the bolt and/or nut to the honeycomb structure, wherein the bolt and/or nut is coupled to a portion of the aircraft propeller.

Clause 4. the aircraft thruster of clause 3, wherein the bolts are not screwed to the male and female conduits.

Clause 5. the aircraft propeller of clause 1, wherein:

the male and/or female conduits being configured to transmit a first force to the honeycomb; and

the male flange portion and/or the female flange portion is coupled to the honeycomb structure over a first region, wherein the first region is sized to transmit the first force such that the honeycomb core does not plastically deform.

Clause 6. an aircraft comprising the aircraft propeller of clause 1, wherein the aircraft comprises:

a body;

a wing coupled to the fuselage; and

an aircraft propeller coupled to the wing and/or the fuselage.

Clause 7. a fastening system for a structure, the fastening system comprising:

a male conduit comprising a male conduit body, wherein:

an externally threaded portion is disposed on at least a first end of the male conduit body,

the male through hole is provided in the male conduit body, an

A male flange portion disposed on the second end of the male conduit body and configured to couple to a first panel of a honeycomb structure and distribute a load to the honeycomb structure when the male flange portion is coupled to the first panel; and

a female conduit comprising a female conduit body, wherein:

an internally threaded portion is disposed on at least a first end of the female conduit body and is configured to be coupled to the externally threaded portion to secure the male and female conduits to the honeycomb,

a female through-hole is provided in the female spool body, an

A female flange portion is disposed on the second end of the female conduit body and is configured to couple to a second panel of the honeycomb and distribute a load to the honeycomb when the female flange portion is coupled to the second panel.

Clause 8. the fastening system of clause 7, wherein the male through-hole comprises a first male through-hole end, a second male through-hole end, and a chamfer at the first male through-hole end.

Clause 9. the fastening system of clause 7, wherein the male and female conduits are mechanically fastened to the honeycomb.

Clause 10. the fastening system of clause 9, wherein the male and female conduits are mechanically fastened to the honeycomb without the need for adhesive.

Clause 11. the fastening system of clause 9, further comprising:

a nut secured to the shank of the bolt.

Clause 12. the fastening system of clause 11, wherein the bolts are not threaded into the male and female conduits.

Clause 13. the fastening system of clause 11, wherein the male and/or female flanges are configured to distribute loads received from the bolts and/or nuts to the honeycomb structure.

Clause 14 the fastening system of clause 9, further comprising the honeycomb, wherein the honeycomb comprises the first panel, the second panel, and a honeycomb core disposed between the first panel and the second panel.

Clause 15. the fastening system of clause 11, wherein the bolt and/or nut is configured to be coupled to an auxiliary structure of an aircraft.

Clause 16. the fastening system of clause 7, wherein:

the male flange portion and/or the female flange portion are configured to couple to the honeycomb structure over a first area, wherein the first area is sized to transmit the first force such that the honeycomb core does not plastically deform.

Clause 17. the fastening system of clause 7, wherein the male and/or female conduits comprise a coefficient of thermal expansion substantially similar to the coefficient of thermal expansion of the honeycomb.

Clause 18. the fastening system of clause 17, wherein the honeycomb structure comprises a first material, the male and/or female conduits comprise the first material, and the first material comprises a metallic material and/or a composite material.

Clause 19. an aircraft including the fastening system of clause 7, wherein the aircraft includes:

a body;

a wing coupled to the fuselage; and

an aircraft propeller coupled to the wing and/or the fuselage and including a core engine and a thrust reverser, wherein the thrust reverser includes an inner wall positioned proximate to the core engine, the inner wall including:

A fastening system disposed within the bore, wherein a male flange portion is coupled to the first panel and a female flange portion is coupled to the second panel, and an internal threaded portion is coupled to an external threaded portion to fasten male and female conduits to the honeycomb.

Clause 20. a method of assembling the fastening system of clause 7, the method comprising:

inserting the female wire tube into the bore of the honeycomb structure;

inserting the male conduit into the cells of the honeycomb; and

the male and female bobbins are screwed together to a torque value.

The above examples illustrate but do not limit the invention. It should also be understood that numerous modifications and variations are possible in accordance with the principles of the present invention. Accordingly, the scope of the invention is to be limited only by the following claims.

Claims

1. An aircraft propeller (100), comprising:

a core engine (248); and

a thrust reverser including an inner wall positioned proximate to the core engine (248), the inner wall including:

a honeycomb structure comprising a first panel (360), a second panel (362), a honeycomb core (358) disposed between the first panel (360) and the second panel (362), and a cell (132), and

a fastening system disposed within the aperture (132), the fastening system comprising:

a male conduit (350) comprising:

a male-type through-hole (474),

a male shank portion comprising an externally threaded portion disposed on at least a first end of the male conduit,

a male flange portion (472) disposed on a second end of the male conduit, coupled to the first panel (360), and configured to distribute a load to the honeycomb structure; and

a male shoulder disposed between the male shank portion and the male flange portion and contacting one side of the first panel to transfer a first support load to the first panel; and

a female conduit (352) comprising:

a female-type through hole 584,

a female handle portion comprising an internally threaded portion disposed within the female throughbore and on at least a first end of the female spool, wherein the female handle portion is coupled to the externally threaded portion to secure the male spool (350) and the female spool (352) to the honeycomb structure,

a female flange portion (580) disposed on a second end of the female conduit, coupled to the second panel (362), and configured to distribute a load to the honeycomb structure, an

A female shoulder disposed between the female handle portion and the female flange portion and contacting one side of the second panel to transfer a second support load to the second panel.

2. The aircraft thruster (100) of claim 1, the fastening system further comprising:

a bolt (354) including a head and a shank and disposed through the male through-hole (474) and the female through-hole (584); and

a nut (356) secured to the shank of the bolt (354), wherein the male flange and/or the female flange are configured to distribute loads received from the bolt (354) and/or the nut (356) to the honeycomb structure, wherein the bolt (354) and/or the nut (356) are coupled to a portion of the aircraft propeller (100).

3. The aircraft thruster (100) of claim 2, wherein the bolts (354) are not screwed into the male (350) and female (352) conduits.

4. The aircraft thruster (100) of any one of claims 1-3, wherein:

the male conduit (350) and/or the female conduit (352) being configured to transmit a first force to the honeycomb; and

the male flange portion (472) and/or the female flange portion (580) are coupled to the honeycomb structure over a first area, wherein the first area is sized to transmit the first force such that the honeycomb core does not plastically deform.

5. A fastening system for a structure, the fastening system comprising:

a male conduit (350) comprising:

a male-type through-hole (474),

a male flange portion (472) disposed on a second end of the male conduit and configured to couple to a first panel (360) of a honeycomb structure and distribute a load to the honeycomb structure when the male flange portion (472) is coupled to the first panel (360); and

a female conduit (352) comprising:

a female-type through hole 584,

a female handle portion comprising an internally threaded portion disposed within the female throughbore and on at least a first end of the female spool, wherein the female handle portion is configured to couple to the externally threaded portion to secure the male spool (350) and the female spool (352) to the honeycomb structure,

a female flange portion (580) disposed on a second end of the female conduit and configured to couple to a second panel (362) of the honeycomb and distribute a load to the honeycomb when the female flange portion (580) is coupled to the second panel; and

6. A fastening system for a structure as claimed in claim 5, wherein the male through-hole (474) comprises a first male through-hole end, a second male through-hole end and a chamfer (476) at the first male through-hole end.

7. The fastening system for a structure of claim 5, wherein:

the male flange portion (472) and/or the female flange portion (580) are configured to couple to the honeycomb structure over a first area, wherein the first area is sized to transmit the first force such that the honeycomb core does not plastically deform.

8. The fastening system for a structure of claim 5 wherein the male (350) and/or female (352) conduits include a coefficient of thermal expansion substantially similar to that of the honeycomb.

9. A fastening system for a structure according to claim 8, wherein the honeycomb structure comprises a first material, the male (350) and/or female (352) conduits comprise the first material, and the first material comprises a metallic material and/or a composite material.

10. An aircraft comprising a fastening system for a structure according to any one of claims 5-9, wherein the aircraft comprises:

a body;

a wing coupled to the fuselage; and

an aircraft propeller (100) coupled to the wing and/or the fuselage and including a core engine (248) and a thrust reverser, wherein the thrust reverser includes an inner wall positioned proximate to the core engine (248), the inner wall including:

a honeycomb structure comprising a first panel (360), a second panel (362), a honeycomb core disposed between the first panel (360) and the second panel, and a cell (132), and

the fastening system disposed within the bore (132), wherein the male flange portion (472) is coupled to the first panel and the female flange portion (580) is coupled to the second panel and the internal thread portion is coupled to the external thread portion to fasten the male conduit (350) and the female conduit (352) to the honeycomb.